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Featured researches published by Christopher B. O'Brien.


The New England Journal of Medicine | 1990

A Randomized, Controlled Trial of Interferon Alfa-2b Alone and after Prednisone Withdrawal for the Treatment of Chronic Hepatitis B

Robert P. Perrillo; Eugene R. Schiff; Gary L. Davis; Henry C. Bodenheimer; Karen L. Lindsay; John A. Payne; Jules L. Dienstag; Christopher B. O'Brien; Carlo H. Tamburro; Ira M. Jacobson; Sampliner Re; David Feit; Jay H. Lefkowitch; Mary C. Kuhns; Carlton Meschievitz; Bharati Sanghvi; Janice K. Albrecht; Alexandra L. Gibas

Abstract Background and Methods. Chronic hepatitis B is a common and often progressive liver disorder for which there is no accepted therapy. To assess the efficacy of treatment with interferon, we randomly assigned patients with chronic hepatitis B to one of the following regimens: prednisone for 6 weeks followed by 5 million units of recombinant interferon alfa-2b daily for 16 weeks; placebo followed by 5 million units of interferon daily for 16 weeks; placebo followed by 1 million units of interferon daily for 16 weeks; or observation with no treatment. Results. Hepatitis B e antigen and hepatitis B viral DNA disappeared from serum significantly more often in the patients given prednisone plus interferon (16 of 44 patients, or 36 percent) or 5 million units of interferon alone (15 of 41; 37 percent) than in the untreated controls (3 of 43; 7 percent; P<0.001); the difference between those given 1 million units of interferon (7 of 41; 17 percent) and the controls was not significant. The strongest indep...


Gastroenterology | 1993

Pathological diagnosis of chronic hepatitis C: A multicenter comparative study with chronic hepatitis B

Jay H. Lefkowitch; Eugene R. Schiff; Gary L. Davis; Robert P. Perrillo; Karen L. Lindsay; Henry C. Bodenheimer; Luis A. Balart; Terryl J. Ortego; John A. Payne; Jules L. Dienstag; Alexandra L. Gibas; Ira M. Jacobson; Carlo H. Tamburro; William D. Carey; Christopher B. O'Brien; Sampliner Re; David H. Van Thiel; David Feit; Janice K. Albrecht; Carlton Meschievitz; Bharati Sanghvi; Roger D. Vaughan

BACKGROUND Hepatic histological responses described in hepatitis C virus (HCV) infection include bile duct damage, lymphoid follicles and/or aggregates in portal tracts, large- and small-droplet fat, Mallory body-like material in hepatocytes, liver cell dysplasia and multinucleation, and activation of sinusoidal inflammatory cells. The specificity of these lesions for HCV infection is uncertain. METHODS In two multicenter trials of recombinant interferon alfa therapy for chronic hepatitis C and B, the frequency of these eight lesions in pretherapy and posttherapy liver biopsy specimens was examined to determine the set of features, if any, that distinguishes HCV from hepatitis B virus (HBV) infection. The lesions were scored in 317 HCV biopsy specimens and 299 HBV specimens. RESULTS Stepwise logistic regression determined a set of three features more likely to be seen in HCV than in HBV infection: bile duct damage [odds ratio (OR), 4.7; 95% confidence interval (Cl), 1.8-12.3], lymphoid follicles and/or aggregates (OR, 2.4; 95% Cl, 1.2-4.7), and large-droplet fat (OR, 2.4; 95% Cl, 1.4-4.1). A fourth lesion, Mallory body-like material, was seen only in HCV biopsy specimens (OR, 71.6; 95% Cl, 4.4-996.1). CONCLUSIONS These four histological lesions are useful pathological parameters in the diagnosis of liver disease caused by HCV.


Transplantation | 2004

Treatment of established recurrent hepatitis C in liver-transplant recipients with pegylated interferon-alfa-2b and ribavirin therapy

Guy W. Neff; Marzia Montalbano; Christopher B. O'Brien; Seigo Nishida; Kamran Safdar; Pablo A. Bejarano; Amr S. Khaled; Phillip Ruiz; Gabriella Slapak-Green; Mei Lee; Jose Nery; Maria De Medina; Andreas G. Tzakis; Eugene R. Schiff

Introduction. The management issues of transplant patients with hepatitis C virus (HCV) are complex, and interferon therapy is often ineffective. We present data from a retrospective review in liver-transplant recipients suffering from HCV recurrence that were treated with pegylated alpha-2b interferon and ribavirin. Methods. A retrospective review of transplant recipients that received combination pegylated alpha-2b interferon (1.5 mcg/kg/wk) and ribavirin (400–600 mg/day) therapy intended for at least 48 weeks. Complications were recorded and included neutropenia (<750 cells), anemia (hemoglobin <8 g) with and without treatment consisting of blood transfusions, erythropoietin, or dose reduction of ribavirin, and depression. The diagnosis of HCV recurrence was determined by an increase in liver chemistries, histopathologic findings with inflammation along with viral recurrence using the COBAS AMPLICOR HCV test. Results. Fifty-seven liver-transplant recipients were included, 29 naïve (group 1) to therapy and 28 nonresponders (group 2) to at least 6 months of interferon and ribavirin therapy. Eight (27.6%) patients in group 1 and six (21%) patients in group 2 were HCV nondetectable at the end of 48 weeks of therapy. Ribavirin therapy was decreased in 13 of 29 (45%) for group 1 and 11 of 28 (39%) in group 2. Therapeutic interventions were 4 of 57 (7%) blood transfusions, 23 of 57 (40%) erythropoietin, and 17 of 57 (30%) filgrastim. Conclusion. Combination pegylated interferon with ribavirin appears to effective therapy in HCV recurrence and in HCV nonresponsive to interferon and ribavirin. This data reveals the difficulty and caution that must be taken when treating HCV-R liver-transplant recipients with combination pegylated alpha-2b interferon and ribavirin therapy.


Transplantation | 2004

A retrospective review of liver transplant patients treated with sirolimus from a single center: an analysis of sirolimus-related complications.

Marzia Montalbano; Guy W. Neff; Noriyo Yamashiki; Douglas Meyer; Marina Bettiol; Gabriella Slapak-Green; Phillip Ruiz; Emory Manten; Kamran Safdar; Christopher B. O'Brien; Andreas G. Tzakis

Background. Sirolimus (SRL) is a powerful immunosuppressant used primarily in calcineurin inhibitors (CNI)-related nephrotoxicity. However, reports of drug-related side effects are increasing. The aim of our report is to review the frequency and timing of these complications within our transplant patient population. Methods. We retrospectively reviewed the medical records of liver-transplanted patients treated with sirolimus between November 1998 and April 2002. The data collected included SRL serum levels, frequency of reported and documented SRL-related side effects, and survival outcomes. Statistical evaluation included Pearson chi-square and the Fisher’s exact tests. Results. Overall, 205 patients were identified, with 30 patients removed from the analysis for different reasons. Of the remaining 175 patients, 91 (52%) patients developed a complication other than an increase in serum triglycerides and/or cholesterol. The most frequent complications were: bilateral lower extremity edema (57.1%), dermatitis (25.3%), oral ulcers (24.2%), joint pain (23.0%), pleural effusion (16.5%) and increase in abdominal girth (9.9%). Other complications included: generalized edema (5.5%), pericardial effusion (5.5%), facial edema (2.2%), and upper extremity edema (1.3%). In addition, we reported two cases of hepatic artery thrombosis, one case of wound dehiscence with evisceration that required surgical repair, and one case of skin cancer. Interestingly, we found that a previous history of myocardial ischemia correlates with the development of SRL side effects. Conclusions. SRL is a powerful immunosuppressant but not devoid of side effects. These results have elevated our level of suspicion when instituting SRL and may help with early recognition and prevention of drug related complications.


Liver Transplantation | 2004

Reliability of histopathologic assessment for the differentiation of recurrent hepatitis C from acute rejection after liver transplantation

Arie Regev; Enrique G. Molina; Rosana Moura; Pablo A. Bejarano; Amr S. Khaled; Phillip Ruiz; Kris Arheart; Mariana Berho; Cinthia B. Drachenberg; Patricia Mendez; Christopher B. O'Brien; Lennox J. Jeffers; Andreas G. Tzakis; Eugene R. Schiff

Histopathologic assessment is considered essential for the differentiation of recurrent hepatitis C (RHC) from acute cellular rejection (ACR) after liver transplantation (LT); however, there is limited information regarding its reliability. The aim of this study was to determine the interobserver and intraobserver agreement of the histopathologic diagnosis of RHC vs. ACR, and to determine the reliability of specific histopathologic features for the differentiation of RHC from ACR. Liver biopsy specimens from 105 consecutive patients transplanted for hepatitis C virus (HCV)‐related liver disease were studied retrospectively. All the biopsies were performed for evaluation of abnormal liver enzymes within the 1st year after LT. The slides were blindly coded and assessed by 5 liver‐transplant pathologists, practicing at 3 medical centers. The pathologists were asked to render a diagnosis, and determine the severity of the disease. Four of the pathologists were asked to determine the presence and severity of 36 histopathologic features. A total of 34 of the samples were then blindly resubmitted to each of the 4 pathologists to determine the intraobserver agreement. There was a slight agreement (κ = .12) among the 5 pathologists on the histopathologic diagnosis. All 5 pathologists were in agreement on the diagnosis of RHC in only 5 patients (5%) and on the diagnosis of ACR in only 2 patients (2%). The best agreement among any 4 pathologists was fair (κ = .20). Slight to moderate agreement occurred on the main histological features considered to be important in the diagnosis of ACR. Intraobserver agreement ranged from slight (κ = .19) to moderate (κ = .42) among 4 pathologists. In conclusion, the histopathologic differentiation of RHC from ACR after LT had relatively low interobserver and intraobserver agreement rates, and hence showed low reliability. Histopathologic assessment should be used cautiously for the differentiation of RHC from ACR post‐LT. (Liver Transpl 2004;10:1233–1239.)


Liver Transplantation | 2004

Outcomes in liver transplant recipients with hepatitis B virus: Resistance and recurrence patterns from a large transplant center over the last decade

Guy W. Neff; Christopher B. O'Brien; Jose Nery; Norah J. Shire; Marzia Montalbano; Phillip Ruiz; Ciao Nery; Kamran Safdar; Maria De Medina; Andreas G. Tzakis; Eugene R. Schiff; Juan Madariaga

Hepatitis B virus (HBV) recurrence following liver transplantation (LTx) has been controllable primarily with the use of hepatitis B immune globulin (HBIg) and lamivudine (LAM). However, HBV resistance to LAM and/or HBIg has become an increasing problem prompting the use of newer antiviral agents. The purpose of our study was to investigate the association between therapy, HBV breakthrough, and allograft / patient survival in HBV‐positive liver transplant recipients. We performed a retrospective review of the medical records of patients that were transplanted for HBV from June 1994 to May 2003. A total of 92 patients, positive for either hepatitis B surface antigen (HBsAg) or HBV deoxyribonucleic acid (DNA) pretransplant, received LAM monotherapy or HBIg (6 months) plus LAM therapy post–liver transplant. HBV breakthrough post‐LTx was noted in 14 patients. All patients had detectable HBV DNA prior to liver transplantation; none of the patients that were HBV DNA negative prior to transplant had detectable HBV DNA posttransplant. Of these 14, 9 patients (64%) were switched from LAM to adefovir dipivoxil (ADF) and 5 patients (36%) to tenofovir disoproxil fumarate (TNV). In conclusion, pre‐LTx HBV viremia should be considered in planning post‐LTx prophylaxis. Trials to evaluate oral antiviral agents in combination with or without HBIg therapy are needed. (Liver Transpl 2004;10:1372–1378.)


Hepatology | 2014

Randomized, double-blind, controlled study of glycerol phenylbutyrate in hepatic encephalopathy

Don C. Rockey; John M. Vierling; Parvez S. Mantry; Marwan Ghabril; Robert S. Brown; Olga Alexeeva; Igor A. Zupanets; Vladimir Grinevich; Andrey Baranovsky; Larysa Dudar; Galyna Fadieienko; Nataliya Kharchenko; Iryna Klaryts'ka; Vyacheslav Morozov; Priya Grewal; Timothy M. McCashland; K. Gautham Reddy; K. Rajender Reddy; Vasyl Syplyviy; Nathan M. Bass; Klara Dickinson; Catherine Norris; Dion F. Coakley; Masoud Mokhtarani; Bruce F. Scharschmidt; Aijaz Ahmed; Luis A. Balart; B. Berk; Kimberly A. Brown; A. Frolov

Glycerol phenylbutyrate (GPB) lowers ammonia by providing an alternate pathway to urea for waste nitrogen excretion in the form of phenylacetyl glutamine, which is excreted in urine. This randomized, double‐blind, placebo‐controlled phase II trial enrolled 178 patients with cirrhosis, including 59 already taking rifaximin, who had experienced two or more hepatic encephalopathy (HE) events in the previous 6 months. The primary endpoint was the proportion of patients with HE events. Other endpoints included the time to first event, total number of events, HE hospitalizations, symptomatic days, and safety. GPB, at 6 mL orally twice‐daily, significantly reduced the proportion of patients who experienced an HE event (21% versus 36%; P = 0.02), time to first event (hazard ratio [HR] = 0.56; P < 0.05), as well as total events (35 versus 57; P = 0.04), and was associated with fewer HE hospitalizations (13 versus 25; P = 0.06). Among patients not on rifaximin at enrollment, GPB reduced the proportion of patients with an HE event (10% versus 32%; P < 0.01), time to first event (HR = 0.29; P < 0.01), and total events (7 versus 31; P < 0.01). Plasma ammonia was significantly lower in patients on GPB and correlated with HE events when measured either at baseline or during the study. A similar proportion of patients in the GPB (79%) and placebo groups (76%) experienced adverse events. Conclusion: GPB reduced HE events as well as ammonia in patients with cirrhosis and HE and its safety profile was similar to placebo. The findings implicate ammonia in the pathogenesis of HE and suggest that GPB has therapeutic potential in this population. (Clinicaltrials.gov, NCT00999167). (Hepatology 2014;59:1073‐1083)


Liver Transplantation | 2015

Sofosbuvir and simeprevir for treatment of hepatitis C virus infection in liver transplant recipients

Julio A. Gutierrez; Andres F. Carrion; Danny J. Avalos; Christopher B. O'Brien; Paul Martin; Kalyan R. Bhamidimarri; Adam Peyton

Recurrent hepatitis C virus (HCV) infection occurs universally in the allograft in the absence of effective antiviral therapy before liver transplantation (LT). Antiviral therapy with sofosbuvir and simeprevir has proven to be highly effective and well tolerated in the nontransplant setting for treatment of HCV genotype 1 infection; therefore, we sought to evaluate the efficacy and safety of this regimen in LT recipients with recurrent HCV infection. This was a retrospective analysis of a single‐center treatment protocol of patients with HCV genotype 1 infection who received a 12‐week combination regimen of sofosbuvir and simeprevir. Sixty‐one patients (35 with genotype 1a and 26 with genotype 1b) completed treatment with simeprevir and sofosbuvir. Three patients received additional ribavirin. Laboratory data and clinical assessments performed at the baseline, on treatment, at the end of treatment, and 12 weeks after the completion of antiviral therapy [sustained virological response at 12 weeks (SVR12)] were analyzed. The median time after LT was 5.4 years [interquartile range (IQR), 1.9‐8.4 years], and tacrolimus was the most commonly used immunosuppressive agent (80.3%). Overall, SVR12 was achieved in 93.4% [95% confidence interval (CI), 84%‐97%] of LT recipients treated with 12 weeks of sofosbuvir and simeprevir. When they were analyzed according to the HCV subtype, LT recipients with genotype 1b had a 100% SVR12 rate (95% CI, 87%‐100%), whereas SVR12 was 89% (95% CI, 74%‐95%) for those with genotype 1a. Advanced fibrosis (METAVIR F3‐F4) was associated with diminished antiviral efficacy in LT recipients with genotype 1a [SVR12, 67% (95% CI, 39%‐86%); P = 0.01]. Overall, the incidence of adverse events (AEs) was low, and no severe AEs occurred during treatment. In conclusion, treatment with a 12‐week regimen of sofosbuvir and simeprevir was well tolerated and resulted in a high SVR12 rate for LT recipients with recurrent HCV genotype 1 infection. Genotype 1a patients with advanced fibrosis of the allograft were more likely to relapse. Liver Transpl 21:823‐830, 2015.


Liver Transplantation | 2004

Factors that identify survival after liver retransplantation for allograft failure caused by recurrent hepatitis C infection

Guy W. Neff; Christopher B. O'Brien; Jose Nery; Norah J. Shire; Seigo Nishida; Julia delaGarza; Marzia Montalbano; Kamran Safdar; Phillip Ruiz; Eric Rideman; Jose A. Gascon; Andreas G. Tzakis; Juan Madariaga; Steven M. Rudich

Hepatitis C virus (HCV) is becoming the most common indication for liver retransplantation (ReLTx). This study was a retrospective review of the medical records of liver transplant patients at our institution to determine factors that would identify the best candidates for ReLTx resulting from allograft failure because of HCV recurrence. The patients were divided into 2 groups on the basis of indication for initial liver transplant. Group 1 included ReLTx patients whose initial indication for LTx was HCV. Group 2 included patients who received ReLTx who did not have a history of HCV. We defined chronic allograft dysfunction (AD) as patients with persistent jaundice (> 30 days) beginning 6 months after primary liver transplant in the absence of other reasons. HCV was the primary indication for initial orthotopic liver transplantation (OLT) in 491/1114 patients (44%) from July 1996 to February 2004. The number of patients with AD undergoing ReLTx in Groups 1 and 2 was 22 and 12, respectively. The overall patient and allograft survival at 1 year was 50% and 75% in Groups 1 and 2, respectively (P = .04). The rates of primary nonfunction and technical problems after ReLTx were not different between the groups. However, the incidence of recurrent AD was higher in Group 1 at 32% versus 17% in Group 2 (P = .04). Important factors that predicted a successful ReLTx included physical condition at the time of ReLTx (P = .002) and Child‐Turcotte‐Pugh score (P = .008). In conclusion, HCV is associated with an increased incidence of chronic graft destruction with a negative effect on long‐term results after ReLTx. The optimum candidate for ReLTx is a patient who can maintain normal physical activity. As the allograft shortage continues, the optimal use of cadaveric livers continues to be of primary importance. The use of deceased donor livers in patients with allograft failure caused by HCV remains a highly controversial issue. (Liver Transpl 2004;10:1497–1503.)


Journal of Hepatology | 1986

The spectrum of liver disease in the acquired immunodeficiency syndrome.

Stuart C. Gordon; K. Rajender Reddy; Edwin Gould; Robert McFadden; Christopher B. O'Brien; Maria De Medina; Lennox J. Jeffers; Eugene R. Schiff

Abnormal liver chemistries, unexplained fevers, or hepatomegaly prompted 36 liver biopsies on 34 patients with the acquired immunodeficiency syndrome. The most common finding was the presence of hepatic granulomas, seen in 13 of the biopsy specimens. Eight of these granulomas were ill-defined, and 5 were more clearly associated with mycobacterial disease. Portal fibrosis and fatty infiltration were common, but a paucity of significant inflammatory activity was seen despite elevated aspartate aminotransferase levels, perhaps related to the underlying immunoincompetent status. Other noteworthy histopathologic findings included 1 patient each with peliosis hepatis and cryptococcal hepatitis. Electron-microscopic evidence of cytoplasmic tubular structures or viral particles were seen within the hepatocytes of 2 patients. It is concluded that a broad spectrum of hepatic histopathology may be seen in the acquired immunodeficiency syndrome, and that liver biopsy may be diagnostically valuable in the clinical investigation of such patients.

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Guy W. Neff

University of Cincinnati

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